Espresso coffee is made by passing hot water, under pressure, through compressed coffee grounds. Conventionally, the coffee grounds are carried in a filter equipped with a handle, referred to as a portafilter. In order to improve the flavour of the coffee by retarding the flow of hot water through the grounds, the grounds are compacted or compressed into the portafilter or a removable filter basket carried by the portafilter. Most often, this compaction of the ground coffee is done with a manual tamping device. The manual tamper compacts the grounds and creates a smooth upper surface. Compression of the body or puck of ground coffee in the portafilter is important to prevent cracks or fissures from developing in the ground coffee. Such cracks could allow hot water to travel through the portafilter without sufficient contact with the grounds.
The compression of the grounds in the portafilter can also be accomplished with an augur. One type of augur is seen in U.S. Pat. No. 6,095,032. The present invention provides a different compaction mechanism and an alternative shut off mechanism.